A cocktail of recombinant Onchocerca volvulus antigens for serologic diagnosis with the potential to predict the endemicity of onchocerciasis infection

We report here the evaluation of the potential of a serologic test to deter mine the endemicity of onchocercal infection in hyper, meso, and hypoendemi c communities by the detection of antibodies to a cocktail of recombinant a ntigens. Parasitologic parameters of infection prevalence and intensity wer e compared with serologic results. Infection prevalence by serology was con sistently but not significantly higher than that defined by parasitology. D ifferences between the communities defined by microfilarial load (CMFL) and a measurement of Onchocerca volvulus-specific antibody levels (serologic i ndex [SI]) were similar. When stratified by age, differences were more sign ificant in the younger age groups. If a sentinel population of 5-15-year-ol d individuals was used to compare communities, all could be equally ranked by serologic and parasitologic parameters. The SI of the sentinel populatio n gave a better distinction between each community than the SI of the whole and would be sufficiently sensitive to measure the changes in endemicity t hat would be required for onchocerciasis control programs.